639976289832 has 48 divisors (see below), whose sum is σ = 1890839040480. Its totient is φ = 193932208800.

The previous prime is 639976289791. The next prime is 639976289839. The reversal of 639976289832 is 238982679936.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is not an unprimeable number, because it can be changed into a prime (639976289839) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 404024644 + ... + 404026227.

It is an arithmetic number, because the mean of its divisors is an integer number (39392480010).

Almost surely, 2^639976289832 is an apocalyptic number.

It is an amenable number.

639976289832 is an abundant number, since it is smaller than the sum of its proper divisors (1250862750648).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

639976289832 is a wasteful number, since it uses less digits than its factorization.

639976289832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 808050894 (or 808050887 counting only the distinct ones).

The product of its digits is 423263232, while the sum is 72.

The spelling of 639976289832 in words is "six hundred thirty-nine billion, nine hundred seventy-six million, two hundred eighty-nine thousand, eight hundred thirty-two".